416 stainless steel is a martensitic stainless steel grade and this grade can be heat threated. This grade is written as 1.4005 or X12CrS13 according to EN norm and it is written as UNS S41600 according to UNS norm. 1.4005 material is very similar to 410 grade stainless steels. The main difference is the sulfur content of this material. 416 stainless steel has a high sulfur content and this element help this grade to have a good machinability. 416 stainless can be machined very easily and this grade is also a heat threatable grade. The corrosion resistance of 416 material is not so good. But if a heat threatable grade is required and if the machinability is really important, 416 stainless steel will be a really good choice. 1.4005 grade usually used in automotive part production, machine industry and valves.
416, X12CrS13, 1.4005, UNS S41600 Chemical Composition WT %
|1.4005||0.06 - 0.15||max 1.5||max 0.04||0.15 - 0.35||max 1.0||max 0.6||12 - 14|
|Thermal Expansion||9.9 x10^-6 /K|
|Modulus of Elasticity||200 GPa|
|Thermal Conductivity||24.9 W/m.K|
|Electrical Resistivity||0.57 x10^-6 Ω .m|
Full Annealing - Heat to 815-900°C for ½ hour per 25mm of thickness. Cool at 30°C per hour maximum to 600°C and air cool.
Sub-Critical Annealing - Heat to 650-760°C and air cool.
Hardening - Hardened by heating to 925-1010°C, quenching in oil, and tempering to suit the mechanical requirements. See accompanying table.
Condition: Tensile Strength Range (N/mm² or MPa) QT 650: 650 - 850
QT 700: 700 - 850
QT 800: 800 - 950
QT 850: 850 - 1000
QT 900: 900 - 1050
416 has the highest machinability of any stainless steel, at about 85% of that of a free-machining carbon steel. As for most other free-machining stainless steels the improvement in machinability is achieved by addition of sulphur which forms manganese sulphide inclusions